question about extract types

I am going to be brewing an espresso stout on sunday. The recipe I am using calls for 6 lbs light syrup and 3 lbs dark DME. I was looking around in my supplies in the basement and I realized that I already have on hand 6 lbs amber syrup and 3 lbs light DME. I was wondering if this would be adequate, since it's still a combination of light and darker malts? It would really save me some cash which would be great right about now. I know recipes aren't set in stone. Plus I was thinking the roasted barely, chocolate malt, and espresso will still do a decent job of darkening it up. What do you guys think? Use what I've got, or go buy what the recipe calls for?

i always go with light extract and just use the grains for color/flavor. you should be fine, assuming you have enough roasted barley and chocolate malt to do the job.

You're pretty much taking a stout and making it darker. I don't see a problem with that.

Darker extracts tend to be slightly less fermentable than lighter, I believe, so I might consider subbing a little bit of the dark DME with some kind of sugar.